Process and apparatus for treating sausage casings



R. L. ATKINSON Feb. 18,1936.

` PROCESS AND APPARATUS FOR TREATING SAUSAGE CASINGS Filed June 14, 1935J7 Wei@ 7V*4` L. filma? a Patented Feb. 1s, 193s PATENT OFFICE .5

I PROCESS AND APPARATUS FOR TREATING SAUSAGE CASINGS Ralph L. emmen,noi-chester, Mass., assigner to Arthur D. Little, Incorporated,Cambridge, Mass., a corporation of Massachusetts Application 'June 14,1933, Serial No. 675,744

7 Claims. This invention relates toa process and apparatus for treatingcasings adapted to contain food products such as sausages or othermaterials. Such casings may be manufactured in the form of regeneratedseamless cellulose hydrate tubing by an extrusion apparatus as, forexample, that shown in the patent to Cohoe No. 1,163,740, dated December14, 1915, or in the copending application Serial No. 668,714, led May 1,1933, and are delivered therefrom as moist collapsed tubing of Y anydesired length. ,It is a well known property of cellulose hydrate thatit tends, upon drying, to shrink drastically and the primary object ofthis invention is to control and limit positively the shrinking of themoist casing, preferably by employing a mandrel over which the moistcasing is smoothly drawn, andon which the'casing is dried, the amount ofthe shrinking of the casing incident to such drying being limited by itscontact with the mandrel.

' A further object of this invention resides in the employment of anexpansible mandrel which is .collapsed when the casing is drawnthereover, then expanded so that its external periphery is of apredetermined length to insure that the casing when dried thereon shallhave an internal periphery of such length, and ilnally collapsed tofacilitate the removal of the casing.

Other objects of the invention will appear from Q a consideration of thefollowing description and of the drawing which forms a part thereof, andin which: e

Fig. 1 is an elevation illustrating one form of apparatus by which thisinvention can be carried Fig. 2 is an elevation on a larger scale of onend of the expansible mandrel on which the casing is dried; and

Figs. 3 and v4 are cross sectional views of the mandrel in the expandedand contracted condi` tion. Y

The drawing shows one form of apparatus by which the process feature ofthis invention may be carried out, but it will be understood that, whilesuch showing embodies this invention, it is not limitative, and thatother forms may be employed to carry out this process.

A casing A of any desired length after being formed on a suitableapparatus (not shown andv A forming nopart of the present invention) isplaced in a container I0. This casing is in the form of collapsedtubing, has been plasticized by treatment with v-glycer1ne, and is keptmoist until the drying operationforming this invention takes place.suitably supported in a housing I2 upon two or more rollers I4 is anexpansible mandrel I6. The mandrel is constructed of any suitablematerial, preferably of a non-rusting character, such vas stainlesssteel, enameled iron, or aluminum, for example. The outer surface is 5smooth and highly polished and preferably rounded so that it will imparta perfectly smooth inner surface to the portion of the casingscontacting it.

I'he mandrel I6 as shown particularly in Figs. 3 1U and 4 comprises apair of channelled or U- shaped members I8 and 20 of any desired length.The members I8 and 20 are connected by strips 22 preferably, though notnecessarily of the same vlength as the members. 'I'he strips 22 aresecured 15 by bolts 24 to the side walls 26 of the member I8 and areprovided with slots 28 through which pass bolts 30 projecting inwardlyfrom the walls 32 'of the member 20. The separation of the members Iland 20, when the mandrel is expanded, is thus 20 limited by theengagement of the bolts 30 with the bottoms of the slots 28. As shown inthe drawing, the position of the bolts 24 in the member Il may beadjusted to regulate and control the extent of the expansion of themandrel. 25`

The mandrel I6 is expanded by means of an air bag 34 inserted in theinterior of the mandrel and terminating in a valve stem 36 whichprojects from the outer end of the mandrel and through which air may beintroduced by a pump or other 30 suitable means. When the bag 34 isdeflated the member It will movey toward 'the member 20 under the actionof the force of gravity, thus releasing the casing so that it may bedrawn off the mandrel. The members I8 and 20 are pro- 35 vided withlongitudinally extending bosses 38 on which the casing A rests as shownin Fig. 3. At the outer end of the mandrel are provided rollers 40, 42,which coact with suitably supported rollers 44, 4I to guide the casingas it is removed 40" from the collapsed mandrel. The rollers 44, 46l maybe xed in position and the mandrel being supported upon the rollers I4shifted longitudinally to avoid contact between the rollers 40and 42when the mandrel is expanded. 'I'he upper 45 roller 44 may however bemounted in a oating bearing so that it can rise or fall as the mandrelis'expanded or contracted.

In carrying out this invention the leading end of themoist casing in thereceptacle i0, which` 50 is in the form of v a attened tube, is openedin any suitable way as manually or by the employment of a jet of air,slipped over the inner end of the mandrel II which has of course beenpreviously collapsed, and then drawn smoothly along when in ex themandrel until it reaches the outer end. 'Ihe casing is usually muchlonger than the portion y drawn over the mandrel. That portion is nothowever severed from the remainder until, as pointed out below, thedrying operation is completed. The housing I2 is so formed that accesscan be had to the mandrel by providing either a removable cover or`removable wall. -The housing is then closed and the mandrel expandedtothe limit set by the enacting slots u and bons 3u. The moist asing maybe larger than the mandrel ded condition or it may be-smaller in whichcase it is stretched while moist by the expansiofn'of the mandrel. Airat a denite temperature and of a definite condition of humidity is then.supplied to and circulatedv through the housing until the casing hasdried. As pointed out above, the regenerated l.cellulose hydrate ofwhich` the casing A is composed, tends to shrink drastically as it driesand thus the casing is drawn taut about the mandrel (see Fig. 3), sothat the inner periphery of the casing is the same as the outerperipheryy ofthe mandrel. The

'been treated.

bosses 38 reduce the surface area of the mandrel contacted by the casingand also facilitate the drawing of the moist casing over the mandrel.

. When the portion of the casing in the housing has dried about themandrel, the mandrel is collapsed and the dried portion' drawn oi overthe outer end. 'I'he rollers l0, I2, 44 and 46 coact to facilitate thismovement of the casing. .As the dried portion is removed thefollowingmoist por-v tion of the remainder of the casing is at the sametime drawn over the mandrel. Whenfully removed the dry portion issevered, the mandrel expanded and the operation just described is re.

peated until all the casing in the receptacle h as The mandrel may be ofany desired length, depending upon various conditionsthat may exist. Amandrel of from 20 to 25 feet in length has been foundtol bequitesatisfactory. Should it be desired m dry the casing in othervtnan the,

rectangular cross section-shown other'rorms of mandrels may be employed.While thehousing is shown to be providd with a single mandrel,l

it will be understood that a plurality of, mandre1s may be employed.The'rollers I4 are preferably of 'soft rubberl so that they will notdamage the casing.- Suitable meansinot shown) may if desired be providedby .which the "rollers andimandrel are separated leaving the mandrelsupported at the endsonly during the drying stage so that the entirelength of the casing portionv will dry uniformly.

The` broad invention resides. in the drying of l a casing of indefinitelength upon a mandrel over .which it is drawn in a moist condition.l

While Ione form ofu apparatus for practicing this: invention and oneorder of process steps have been described 'it will be understood that Iam not limited thereto and that other forms of apparatus andother ordersof process steps may be employed without departing from the spirit andscope of` this invention asiset forth in the following claims.

v'I'claimzp l 1. The process ofidrying moist tubular casings made ofregenerated cellulose hydrate upon an expansible mandrel, said casingsbeing inthe formd'of, collapsed tubing, indeterminate in. length,

ysociated member,"

during comprising ythe steps of opening one end of the casing, slippingsaid opened end over one end of the mandrel in the contracted condition,draw- 2. The process of drying moist tubular casngs made ofl regeneratedcellulose hydrate upon an expansible mandrel, said casings being in theform of collapsed tubing indefinite in length, comprising the slteps'ofdrawing a portion of said .casing smoothly'lover the mandrel from oneend thereof in the'contracted condition, expanding said mandrel toa'definite extent, permitting the casing to remain upon the mandrel untilit has dried in close contact therewith, contracting the mandrel, anddrawing thel driedportion of the casing oi the mandrel. Y Y `Y 3.Meansfor drying Va sausage casing comprising a housing andan expansiblemandrel within the housing over' which' mandrel the casing is drawnandon-'which it vis allowed to dry,- said mandrel being hollowand including'two relatively movable U-shaped members-and an air bag within themandrel which when inated'separates the members. 4. The processfofdrying moist tubular casings f regenerated cellulose hydrate in the formof seamless tubing Vof indeterminatelengthuponv Va mandrel comprisingthesteps `Vof Vdrawing one end or the casing smoothly over the mandrel,supporting the casingn in predetermined locations on the mandrel,'leaving the intervening 'casing portions unsupported, and permittingthe `casing to dry in closecontact with-the mandrel. 1 f

Y 5. Means-for ,drying4 a-*sausage casing intheV 'formof a hollow;expansible` mandrelover which the casingds1drawn-fordryingthereon, said-mandrel comprising a ypair ofsubstantially telescopically arrangedmembers, anda bag between vthe members adapted'to be separatethe F45members.

' Means forl asausage'- casinginf--the form of a hollow', expansibleimandrel'overV which thek casing is drawn for drying thereon, saidmandrel comprising a pair of relatively movable members,I each of .whichisvprovided'with'on'eor more ridge-like projections along thelength`=thereof, I

l and `a bag between' :the 'members--ladaptedato be inilated to separateA the members;V the Y'casing be-l ing supportedon the projections duringdrying. f`

'1. Means foi'dryingX a,1A `sausage casing inV the form of a hollow,Aexl'iansibleimandrel over which the casing is drawn for drying thereon;said-mandrel comprisingl a" of relatively fmovable, i

YChmliel membersY positioned with their." side flanges extending towardeach other, each of the `members havlngfa ridge-likeprojection along thelength of each corner,tliereotheprojections4 `be-I in'ginclined to4 theandfilangesfofthe' as- I nda'bagbetween tlieiielnbev lrs f' adaptedk tofbe to 'separate'-tlie-members`,

the casing being` supportedfon the `v-prvaiectim s l

